GSK: registrational data support first-line expansion of Jideytro in ROS1‑positive NSCLC

Key efficacy findings

In the registrational, single‑arm phase I/II ARROS‑1 cohort of 94 efficacy‑evaluable, TKI‑naïve patients, zidesamtinib produced a 94% objective response rate (88/94; 95% CI 87–98) and a 15% complete response rate (14/94) after a median follow‑up of 15.2 months. Responses were durable (94% responding at nine months, 86% at 12 months). Progression‑free survival was 90% at 12 months; median PFS and median duration of response were not reached at data cut‑off.

Intracranial activity

Among patients with measurable brain metastases at baseline (n=10), zidesamtinib showed 100% intracranial response (10/10; 95% CI 69–100) with 70% achieving complete clearance of detectable brain tumours (7/10). At 12 months, 78% maintained an intracranial response, and no CNS progression events were observed in patients without baseline brain metastases.

Safety and regulatory context

Treatment‑related adverse events were mostly low grade; the most common (≥15%) were peripheral oedema, weight increase, increased creatine phosphokinase, dysgeusia and AST increase. TRAEs led to dose reductions in 11% of patients and discontinuation in 1%. Data were presented at the 2026 World Conference on Lung Cancer and will support a planned supplemental New Drug Application to the US FDA in 2026 to seek first‑line approval; zidesamtinib was previously approved in July 2026 for patients treated with a prior ROS1 TKI. ARROS‑1 data were cut off 16 April 2026.